This invention relates to an ultrasonic imaging apparatus of a type in which ultrasonic echo information reflecting from an object is utilized for diagnosis.
The ultrasonic imaging apparatus has widely been used in the diagnostic field. In use, it takes a tomogram of an object to be diagnosed, for example, a patient, and uses the tomogram for diagnosis. For taking a tomogram, the apparatus irradiates the patient with ultrasonic waves, receives the echo waves from a target, or an affected part, of the internal tissue of the patient, and converts them into echo signals. Subsequently, the apparatus image processes the echo signals to visualize them as a tomogram, by a monitor.
The conventional ultrasonic imaging apparatus can collect only the tomographic information of the object. By the tomographic information, it is possible to locate the affected part, but difficult to know the type and condition of the affected part. For exact diagnosis, it is essential to collect the information representing the type and conditions of the affection as well as the tomographic information.
Intensive studies on how to collect such information have been made by the inventor. In the studies, the inventor took notice of the scattered ultrasonic component in the ultrasonic wave.
The ultrasonic beams projected toward the affected part of the patient are inevitably attenuated and scattered as it travels. This is true for the echo beam from the affected part. This fact makes it very difficult to exactly detect the scattered ultrasonic component. The studies of the inventor broke through this difficulty to succeed in precise detection of the scattered ultrasonic component.